下列叙述中，正确的是______。A．高级语言编写的程序的可移植性差 B．机器语言就

可以用来证明命题“两个无理数的和仍是无理数”为假命题的反例是（    ）。

下列何种情况下可出现上肢青紫较下肢重（）

A．动脉导管未闭

B．法洛四联症

C．完全性大动脉转位合并动脉导管未闭

D．肺动脉狭窄

E．主动脉狭窄

某设备目前的实际价值8000元，预计残值800元，第一年的设备运行成本为600元，假设设备的年劣化值为200元（年均等），则该设备的经济寿命是（）年。

A．8.5

B．7.5

C．6.5

D．5.5

DOM is a platform- and language- (66) API that allows programs and scripts to dynamically access and update the content, structure and style of WWW documents (currently, definitions for HTML and XML documents are part of the specification). The document can be further processed and the results of that processing can be incorporated back into the presented (67) . DOM is a (68) -based API to documents, which requires the whole document to be represented in (69) while processing it. A simpler alternative to DOM is the event-based SAX, which can be used to process very large (70) documents that do not fit into the memory available for processing.

A．specific

B．neutral

C．contained

D．related

粘土岩极易吸收钻井液中的自由水膨胀而导致（）。

A、井径缩小

B、泥包钻头

C、井斜

D、井漏